The invention relates to the field of amplifier circuits, and more specifically to the field of integrated power amplifier circuits.
Typical power amplifier (PA) technologies utilize multiple integrated circuits in order to provide functionality for amplification, power output control and for stabilization of the PA output signal level due to supply voltage and temperature fluctuations.
It is well appreciated to those skilled in the art of amplifier design that bias currents supplied to the RF signal amplification stages is are an important determinant of the performance of the amplification stages. For example, a bias current supplied to the base of a bipolar transistor acting as a RF signal amplification stage is a major determinant of the amplification performance demonstrated by that bipolar transistor. Selecting and supplying the correct bias current is crucial to optimizing the RF signal amplification characteristics of any transistor amplifier. Moreover, one can appreciate that having control over the bias current supplied to the transistor amplifiers can enable more sophisticated schemes for optimizing the power output characteristics of the transistor amplifier. For example, one might detect output power from a power amplifier and choose to modify the bias current in response to the measured output power. Furthermore, one can envisage other figures of merit associated with the performance of power amplifiers that might be optimized using control over the bias current, such as bias current reduction at lower output powers to improve operating efficiency when RF-induced rectification currents are low.
Of course, such a concept is not new to the art of power amplifier design or their utilization. Open-loop or close-loop control over the performance of a power amplifier through the bias current is well known to those of skill in the art. Moreover, closed loop control has been used to mitigate variations in power amplifier output power performance in response to input control voltages, external temperature changes, or simply to mitigate manufacturing tolerance.
Introducing a degree of control, however, over the performance of power amplifiers through the bias current entails using additional circuitry to convert voltage detection error signals into incremental base voltage changes on the transistors. That is, circuitry is required above and beyond the transistors used for providing RF signal amplification. For example, introducing control over the bias current will require, at a minimum, circuitry for receiving the control signal and for varying the bias current. Numerous circuit block architectures have been discussed in the prior art for achieving thereof.
Furthermore, all existing control architectures employ a substantial die area, and utilize multiple integrated circuit technologies with a net higher manufacturing cost and large associated packaging area. This traditional approach often results in a reduction in operating efficiency, due to the need for in-line coupling circuits, and poor repeatability of results, create more challenging calibration requirements and reduced manufacturing yields.
If is therefore an object of the invention to provide a power amplifier integrated circuit (PAIC) that overcomes the limitations of the prior art by fully integrating such bias and power control features on a single PAIC within a single manufacturing process technology. The PAIC advantageously realizes a reduced die and packaging area over existing solutions. Along with improved RF output signal power control repeatability versus temperature and supply voltage variations.
In accordance with the invention there is provided a power amplifier circuit comprising: an input port for receiving a RF input signal; an output port for providing therefrom a RF output signal, the RF output signal being an amplified version of the RF input signal; a supply voltage input port for receiving a supply voltage; a voltage regulator circuit for receiving the supply voltage and for providing a regulated supply voltage; a first amplification stage having a first gain and for receiving one of a signal derived from the RF input signal and the RF input signal and for providing a first amplified RF signal, the first amplification stage coupled to the voltage regulator circuit for receiving the regulated supply voltage; and, a second amplification stage having a second gain and coupled to the first amplification stage for receiving one of a signal derived from the first amplified RF signal and the first amplified RF signal and coupled to the output port for providing the output signal thereto, the second amplification stage coupled to the supply voltage input port for receiving the supply voltage other than regulated by the voltage regulator circuit.
In accordance with the invention there is provided a method of amplifying a RF input signal to form a RF output signal that is an amplified version of the RF input signal comprising the steps of: receiving the RF input signal; providing a first amplification stage having a first gain; providing a second amplification stage having a second gain; receiving a first supply voltage; regulating the first supply voltage to provide a regulated supply voltage; providing the regulated supply voltage to the first amplification stage; providing the first supply voltage to the second amplification stage; and, amplifying one of a signal derived from the received RF input signal and the received RF input signal using the first amplification stage having the first gain and the second amplification stage having the second gain to form the RF output signal.
In accordance with the invention there is provided a power amplifier circuit comprising: an input port for receiving a RF input signal; an output port for providing therefrom a RF output signal, the RF output signal being an amplified version of the RF input signal; a supply voltage input port for receiving a supply voltage; a voltage regulator circuit for receiving the supply voltage and for providing a regulated supply voltage; a first amplification stage having a first gain for receiving one of a signal derived from the RF input signal and the RF input signal and for providing a first amplified RF signal, the first amplification stage coupled to the voltage regulator circuit for receiving the regulated supply voltage; a second amplification stage having a second gain for receiving one of a signal derived from the first amplified RF signal and the first amplified RF signal and coupled to the output port for providing the output signal thereto, the second amplification stage coupled to the supply voltage input port for receiving the supply voltage, the supply voltage provided to the second amplification stage and other than regulated by the voltage regulator circuit; a temperature sensing circuit disposed for sensing a temperature of the power amplifier circuit and for providing a temperature signal therefrom in dependence upon the sensed temperature of the power amplifier circuit, the temperature signal for provision to the regulator circuit and at least one of the first amplification stage and the second amplification stage; a voltage sensing circuit disposed for sensing a potential of the supply voltage and for providing a sense signal in dependence thereon, the sense signal for provision to at least one of the regulator circuit and the first amplification stage and the second amplification stage; and, a control port coupled to at least one of the voltage regulator circuit and the first amplification stage and the second amplification stage for at least one of respectively controlling the regulated supply voltage and the first gain and the second gain.
In accordance with the invention there is provided a power amplifier circuit comprising: an input port for receiving a RF input signal; an output port for providing a RF output signal therefrom that is an amplified version of the RF input signal; a control port for receiving a control signal; a supply voltage input port for receiving a supply voltage; a temperature sensing circuit for sensing a temperature of the power amplifier circuit and for providing a temperature signal in dependence thereon; a voltage sensing circuit for sensing a potential of a voltage supply and for providing a sense signal in dependence thereon; a first amplification stage having a first gain for amplifying one of a signal derived from the RF input signal and the RF input signal to form a first amplified RF signal, the first amplification stage for receiving at least one of the temperature signal and the sense signal and the control signal and for varying the first gain in dependence thereon; and, a second amplification stage having a second gain for amplifying one of a signal derived from the first amplified RF signal and the first amplified RF signal to form the RF output signal, the second amplification stage for receiving the control signal and other than receiving at least one of the temperature signal and the sense signal for varying the second gain in dependence thereon.
In accordance with the invention there is provided a method of operating a multi amplification stage amplifier circuit comprising the steps of: receiving of a control signal having a control signal magnitude; providing a first amplification stage having a first gain; receiving one of a signal derived from a RF input signal and a RF input signal for amplification using the first amplification stage; amplifying the one of a signal derived from the RF input signal and the RF input signal using the first amplification stage to form a first amplified RF signal, the amplifying of the one of a signal derived from the RF input signal and the RF input signal performed in conjunction with a step of compensating of the first amplification stage for at least two of temperature and supply voltage and control signal magnitude; providing a second amplification stage having a second gain; receiving of the first amplified RF signal using the second amplification stage; and, amplifying one of a signal derived from the first amplified RF signal and the first amplified signal using the second amplification stage to form a RF output signal, the amplifying of the one of a signal derived from the first amplified RF signal and the first amplified signal performed in conjunction with a step of other than compensating of the second amplification stage for at least one of temperature and supply voltage fluctuations.
In accordance with the invention there is provided a power amplifier circuit comprising: an input port for receiving a RF input signal; an output port for providing a RF output signal therefrom that is an amplified version of the RF input signal; a control port for receiving a control signal; a supply voltage input port for receiving a supply voltage; a temperature sensing circuit for sensing a temperature of the power amplifier circuit and for providing a temperature signal in dependence thereon; a voltage sensing circuit for sensing a potential of a voltage supply and for providing a sense signal in dependence thereon; a first amplification stage having a first gain and for amplifying one of a signal derived from the RF input signal and the RF input signal to form a first amplified signal, the first amplification stage for receiving at least one of the temperature signal and the sense signal and the control signal and for varying the first gain in dependence thereon; and, a second amplification stage having a second gain and for amplifying one of a signal derived from the first amplified signal the first amplified signal, the second amplification stage for receiving at least one of the control signal and the temperature signal and the sense signal for varying the second gain in dependence thereon, the second amplification stage coupled directly to the supply voltage input port.
In accordance with the invention there is provided a method of operating a poly stage amplifier circuit comprising the steps of: providing of a first amplification stage having a first gain and for receiving one of a signal derived from a RF input signal and a RF input signal for amplification; amplifying the one of a signal derived from the RF input signal and the RF input signal using the first amplification stage to form a first amplified signal, the amplifying of the one of a signal derived from the RF input signal and the RF input signal performed in conjunction with a step of compensating of the first amplification stage for at least one of temperature and supply voltage fluctuation and control signal magnitude; providing of a second amplification stage having a second gain and for receiving one of a signal derived from the first amplified signal and the first amplified signal; supplying the supply voltage to the second amplification stage without a substantial voltage drop between a potential of the supply voltage and that received by the second amplifying stage; and, amplifying the signal derived from the first amplified signal and the first amplified signal using the second amplification stage to form a RF output signal, the amplifying of the signal derived from the first amplified signal and the first amplified signal performed in conjunction with a step of compensating of the second amplification stage for at least one of temperature and supply voltage fluctuations.
In accordance with the invention there is provided an amplifier circuit for receiving an input signal for amplification comprising: an input port for receiving a RF input signal; an output port for providing a RF output signal therefrom that is an amplified version of the RF input signal; a control port for receiving a control signal; a supply voltage input port for receiving a supply voltage; a regulator circuit for receiving the supply voltage and for providing a regulated supply voltage in dependence upon at least one of a temperature of the amplifier circuit, the supply voltage, and the regulated supply voltage, where at least one of the temperature signal, the supply voltage and the regulated supply voltage are provided to the regulator circuit using a direct feedback path; at least a first amplification stage and a second amplification stage, the at least a first amplification stage and the second amplification stage coupled to at least one of the supply voltage and the regulated supply voltage, the first amplification stage for receiving one of a signal derived from the RF input signal and the RF input signal and for providing a first amplified signal, to the second amplification stage, the second amplification stage for amplifying a signal derived from the first amplified signal and the first amplified signal to form the RF output signal.
In accordance with the invention there is provided a method of operating a multi stage amplifier circuit comprising the steps of: receiving a RF input signal; receiving a supply voltage; receiving a control signal; receiving at least one of a temperature signal related to a temperature of the amplifier circuit and a sense signal related to the supply voltage; regulating the received supply voltage to form a regulated supply voltage in dependence upon the received at least one of temperature signal and sense signal; providing a first amplification stage having a first gain; providing a second amplification stage having a second gain; providing the regulated supply voltage to at lease one of the first amplification stage and the second amplification stage; and, amplifying one of a signal derived from the received RF input signal and the received RF input signal using the first amplification stage and the second amplification stage to form a RF output signal that is an amplified version of the one of a signal derived from the received RF input signal and the RF input signal.